JP2005265001A - Solenoid valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate an unnecessary space, and to miniaturize a solenoid portion by decreasing a clearance between coils laminated on a coil bobbin. <P>SOLUTION: The solenoid valve comprises a movable core 40 sucked by a fixed core portion 54 under energizing action to a coil 34, a solenoid portion 12 having a return spring 36 for returning the movable core 40 to an initial position, a shaft 38 coupled to the movable core 40 and displacing integrally with the movable core 40, and a valve mechanism portion 16 having a ball 32 for opening/closing a communicating passage 22 between an inlet port 20 and an outlet port 24 under displacement action of the shaft 38. The coil 34 is formed to have a square cross-section. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electromagnetic valve capable of displacing a valve body by attracting a movable iron core to a fixed iron core by electromagnetic force generated under the excitation action of a solenoid coil.

  2. Description of the Related Art Conventionally, an electromagnetic valve that displaces a valve body by attracting a movable iron core to a fixed iron core by an electromagnetic force generated under the excitation action of a solenoid coil has been used.

  For example, Patent Document 1 discloses a solenoid valve assembly configured by winding the solenoid coil a plurality of times around a coil bobbin. In this case, the solenoid coil is formed by winding a coil having a circular cross section over multiple layers.

JP-A-60-125478

  However, in the solenoid valve assembly disclosed in Patent Document 1, since the solenoid coil has a circular cross section, a gap is generated between the coils stacked on the coil bobbin, as shown in FIG. For this reason, a large number of gaps are formed along the axial direction and the radially outward direction of the coil bobbin by winding a solenoid coil having a circular cross section around the coil bobbin a plurality of times.

  Accordingly, when a solenoid coil having a circular cross section is wound around the coil bobbin a plurality of times, an extra space portion is created by accumulating a large number of gaps generated between the cross sections of the stacked circular solenoid coils. There is a problem that the shape of the entire solenoid coil completed by being wound around the coil bobbin is enlarged. As a result, there is a problem that the entire solenoid portion including the solenoid coil inevitably increases in size.

  The present invention has been made in consideration of the above-mentioned problems, and by reducing the gap between the coils stacked on the coil bobbin, it is possible to eliminate the extra space and achieve the miniaturization of the solenoid unit. It aims to provide a simple solenoid valve.

  In this section, for ease of understanding, the reference numerals in the accompanying drawings will be described in parentheses. However, the contents described in this section should not be construed as being limited to those given the reference numerals.

The present invention relates to a solenoid valve body including a valve body (18) having an inlet port (20) and an outlet port (24) through which a pressure fluid flows, and a housing (14);
A coil (34) disposed inside the housing and wound around a coil bobbin (56), a yoke (62) connected to one end of the housing, and a fixed core portion (54) under an energizing action on the coil A solenoid part (12) having a movable core (40) to be sucked by the motor, and a spring member (36) interposed between the fixed core part and the movable core to return the movable core to an initial position;
A valve having a shaft (38) connected to the movable core and displaced integrally with the movable core, and a valve body (32) for opening and closing a communication path between the inlet port and the outlet port under the displacement action of the shaft. A mechanism (16);
With
The coil is formed in a square cross section.

  According to the present invention, since the cross-sectional shape of the coil wound around the coil bobbin is a square or a rectangle, the gap generated between the stacked coils can be made extremely small. Therefore, the winding space of the coil wound around the coil bobbin can be reduced.

  In this case, since a high current value can be ensured by reducing the resistance value when the coil is energized, the coil can be suitably used as a vehicle-mounted solenoid valve with a limited minimum applied voltage.

  In addition, an annular flange protruding radially outward is formed only at one end or the other end along the axial direction of the coil bobbin, and the one end or the other end where the annular flange is not formed is made of resin. It is good to coat | cover with the sealing body formed with the material. The length dimension of the coil bobbin in the axial direction is shortened by the thickness dimension of the flange, which can contribute to miniaturization of the solenoid portion. In addition, the coil is stably protected by covering the portion of the coil where the flange is not formed with a sealing body made of a non-conductive material.

  Furthermore, since the non-magnetic layer is formed on the entire outer surface of the movable core, for example, by surface modification, it can function as a magnetic gap in a magnetic circuit generated by energizing the coil.

  Furthermore, since the nonmagnetic layer is formed on the entire outer surface of the movable core, it can be easily formed to have a predetermined dimension by managing the outer diameter of only the movable core. Therefore, the magnetic gap formed by the clearance between the yoke and the movable core can be managed with high accuracy, and extremely good magnetic characteristics can be obtained.

  According to the present invention, the following effects can be obtained.

  That is, by making the cross-sectional shape of the coil wound around the coil bobbin square or rectangular, the clearance between the coils stacked on the coil bobbin is reduced, and the extra space is eliminated, thereby reducing the size of the solenoid part. Can be planned.

  Preferred embodiments of the electromagnetic valve according to the present invention will be described in detail below with reference to the accompanying drawings.

  In FIG. 1, reference numeral 10 indicates a solenoid valve according to an embodiment of the present invention.

  The electromagnetic valve 10 includes a housing 14 having a solenoid portion 12 provided therein, and a valve body 18 integrally coupled to the housing 14 and provided with a valve mechanism portion 16 therein. The housing 14 and the valve body 18 function as a solenoid valve main body. The housing 14 is formed of a magnetic material such as SUM (JIS standard), and the valve body 18 is made of, for example, aluminum. It may be formed of a nonmagnetic material.

  The valve body 18 is formed of a substantially cylindrical body, and an inlet port 20 into which a pressure fluid (for example, pressure oil) is introduced is formed at a lower end portion of the valve body 18, and a side slightly above the inlet port 20 is formed. An outlet port 24 that communicates with the inlet port 20 via the communication path 22 is formed in the part. Above the outlet port 24, a discharge port 28 communicating with a space portion 26 penetrating in the axial direction inside the valve body 18 is formed.

  A first valve seat member 29 having a communication passage 22 is fitted to the inner wall of the valve body 18 adjacent to the inlet port 20. The communication passage 22 is blocked by sitting on a lower seat portion 30 formed in the first valve seat member 29, and the communication passage 22 is separated from the lower seat portion 30 by being separated from the lower seat portion 30. A ball 32 that functions as a valve body to be opened is provided.

  The ball 32 may be formed of bearing steel such as SUJ (JIS standard), for example. When a coil 34 (described later) of the solenoid unit 12 is in a non-energized state, the ball 32 is seated on the lower side seating unit 30 via a shaft 38 pressed by a spring force of a return spring 36 described later. is there.

  A shaft 38 that is displaceable along the axial direction is disposed in the space 26 inside the valve body 18, and the shaft 38 has a spherical contact surface (not shown) and has a small diameter that contacts the ball 32. The shaft portion 38a includes a diameter-expanded portion 38b that is expanded through a tapered portion that is continuous with the small-diameter shaft portion 38a, and a connecting portion 38c that is press-fitted into a stepped hole portion 42 of the movable core 40 described later. The The shaft 38 may be made of a nonmagnetic material such as SUS304 (JIS standard).

  A second valve seat member 44 is fitted on the inner wall of the intermediate portion of the valve body 18 adjacent to the ball 32 via an annular step. At the center of the bottom surface of the second valve seat member 44, a through hole 46 for inserting the small-diameter shaft portion 38a of the shaft 38 is formed, and an upper portion on which the ball 32 spaced from the lower seat portion 30 is seated. A side seating portion 48 is formed.

  In addition, the outer peripheral surface of the valve body 18 is provided with first to third seal members 50a to 50c that are arranged at predetermined intervals along the axial direction and are mounted in an annular groove.

  The solenoid portion 12 is housed in the housing 14 having a fixed core portion 54 formed by a recessed portion 52 that is recessed by a predetermined length along the axial direction of the shaft 38, and is wound around a coil bobbin 56. The coil 34 and the movable core 40 which consists of a substantially cylindrical body and in which the stepped hole part 42 penetrated along the axial direction was formed in the center part. The coil bobbin 56 is formed of, for example, a resin material, and has annular flanges 57a and 57b projecting by a predetermined length in the radially outward direction at both ends along the axial direction.

  As shown in FIG. 3, the coil 34 is made of a square wire having a square cross section. By forming the coil 34 to have a square cross section, contact between the coils 34 wound around the coil bobbin 56 becomes surface contact, so that the coil 34 is stably and aligned at a predetermined position. Thereby, as shown in FIG. 4, one flange 57a (57b) of the coil bobbin 56 can be made unnecessary. By eliminating the need for the one flange 57a (57b), the axial dimension of the entire solenoid portion 12 can be shortened and the size can be reduced.

  In addition, when a coil according to the related art formed in a circular cross section as shown in FIG. 10 is wound around a coil bobbin, a force that collapses toward the flange acts due to the tension when winding the coil. In the coil 34 having a square cross section, the force that collapses toward the flange 57a (57b) due to the surface contact between the coils 34 does not work, so that one flange 57a (57b) can be eliminated.

  In addition, as FIG.5 and FIG.6 shows, you may use the other coil 34a which consists of a flat conducting wire formed in the cross-sectional rectangle. In this case, the coil 34 having a square cross section can be set with a smaller winding space than the coil 34a having a rectangular cross section. Furthermore, in the coil 34 having a square cross section, since the peripheral dimension of the cross section can be made smaller than that of the coil 34a having a rectangular cross section, the cross-sectional area of the insulating coating on the coil 34 can be set small.

  The movable core 40 is formed with a passage 58 that is orthogonal to the axial direction and communicates with a stepped hole 42 in the center. The passage 58 fills a clearance 60 between the fixed core portion 54 and the movable core 40. Has a function of releasing the pressurized fluid (pressure oil).

  The fixed core portion 54 is integrally formed with the housing 14 by, for example, pressing. In the present embodiment, the fixed core portion 54 can be hollowed by the concave portion 52 of the housing 14 as compared with a case where a cylindrical core (not shown) is fixed to the housing 14 to be a fixed core, thereby reducing the weight. At the same time, the manufacturing cost can be reduced.

  Further, the solenoid portion 12 has a return spring (spring member) having one end portion engaged with the inner wall surface of the fixed core portion 54 and the other end portion engaged with the step portion of the stepped hole portion 42 of the movable core 40. ) 36 and a yoke 62 connected to one end of the housing 14 and surrounding the outer peripheral surface of the movable core 40. When the movable core 40 is pressed in a direction away from the fixed core portion 54 by the spring force of the return spring 36 and is in an off state where the coil 34 of the solenoid portion 12 is not energized, the movable core 40 is fixed to the movable core 40. A predetermined clearance 60 is formed between the core portion 54 (see FIG. 1).

  The movable core 40 is formed of a substantially cylindrical body, and a nonmagnetic layer 64 having a predetermined depth is formed on the entire outer surface (see FIGS. 7 and 8). Further, the outer peripheral surface of the end portion of the movable core 40 facing the fixed core portion 54 gradually increases in diameter as compared with other portions of the movable core 40 and has substantially the same diameter as the fixed core portion 54. An enlarged diameter portion 66 is provided.

  In this case, even though the yoke 62 is interposed between the coil bobbin 56 and the movable core 40 by forming an enlarged diameter portion 66 having substantially the same diameter as the fixed core portion 54 with respect to the movable core 40. Accordingly, the area of the movable core 40 facing the fixed core portion 54 can be increased, and the magnetic characteristics can be improved.

  The nonmagnetic layer 64 of the movable core 40 is formed by performing a surface modification process such as a carburizing process and / or a nitriding process, for example. This carburizing treatment and nitriding treatment are advantageous in that post-treatment is unnecessary by suppressing the dimensional change of the movable core 40 because the magnetic permeability is modified by surface treatment at a relatively low temperature.

  Examples of the carburizing treatment include solid carburizing, liquid carburizing (carbonitriding method), gas carburizing, plasma carburizing, etc., and the nitriding treatment includes gas nitriding, liquid nitriding (salt bath nitriding), soft nitriding, ion Nitriding and the like are included.

  Further, in order to form the nonmagnetic layer 64 on the outer surface of the movable core 40, for example, an induction hardening process may be performed. When the nonmagnetic layer 64 is formed by performing induction hardening, high-speed heat treatment is possible, and the manufacturing process can be shortened. The method of forming the nonmagnetic layer 64 on the outer surface of the movable core 40 is not limited to the surface modification treatment such as the carburizing treatment, nitriding treatment, and induction hardening treatment. For example, the laser beam is irradiated. It is also possible to use other surface modification treatments such as.

  The movable core 40 may be made of, for example, ferritic stainless steel such as SUS410L or SUS405 (JIS standard), general steel such as S10C (JIS standard), or free-cutting steel material such as SUM (JIS standard). .

  As shown in FIG. 7, when the thickness of the nonmagnetic layer 64 formed on the outer surface of the movable core 40 is thin, the thickness of the nonmagnetic layer 64 is preferably in the range of 10 μm to 30 μm. The thickness T1 is preferably set to 20 μm. At that time, since the magnetic gap generated between the movable core 40 and the yoke 62 can be made extremely small, the magnetic force can be improved, and thus a large attractive force can be obtained. For this reason, in this Embodiment, size reduction can be achieved compared with what generate | occur | produces an equal suction | attraction force.

  Further, as shown in FIG. 8, when the thickness of the nonmagnetic layer 64 formed on the outer surface of the movable core 40 is thick, the thickness of the nonmagnetic layer 64 is in the range of 50 μm to 100 μm. The thickness T2 is preferably set to 75 μm. At this time, since the magnetic gap generated between the movable core 40 and the yoke 62 can be increased, the side force acting between the movable core 40 and the yoke 62 can be suppressed. In this case, for example, a linear solenoid having a low hysteresis characteristic can be obtained by applying to a linear solenoid of a type in which the hysteresis is increased by the side force.

  In addition, durability can be improved by using as the magnetic material which forms the said movable core 40 what contains Cr in 12 weight% or less.

  The yoke 62 includes a cylindrical portion 68 that surrounds the outer peripheral surface of the movable core 40 and extends in the axial direction, and an annular flange portion 70 that protrudes radially outward from the outer peripheral surface of the cylindrical portion 68. Then, the lower end portion of the cylindrical portion 68 is fitted to the spigot portion 72 formed on the inner wall of the valve body 18.

  By fitting the yoke 62 to the inlay portion 72, the assembly of the yoke 62 with respect to the valve body 18 can be satisfactorily maintained, and the assembly accuracy can be improved. The yoke 62 is integrally formed of a magnetic material such as SUM (JIS standard), for example.

  The cylindrical portion 68 is divided into an upper cylindrical portion 68a and a lower cylindrical portion 68b starting from the annular flange portion 70, and the end surface along the axial direction of the upper cylindrical portion 68a is in an off state of the solenoid portion 12. Sometimes it extends to the vicinity of the enlarged diameter portion 66 of the movable core 40, and the end surface along the axial direction of the lower cylindrical portion 68b is substantially flush with the end surface of the movable core 40 when the solenoid portion 12 is on. Is formed.

  Thus, since the length of the section in which the magnetic gap between the yoke 62 and the movable core 40 acts can be kept constant regardless of the on / off operation of the solenoid unit 12, the solenoid unit 12 can be turned on / off. It is possible to prevent the suction force (electromagnetic force) from being affected by the off operation.

  In this case, by forming the lower cylindrical portion 68b in the yoke 62, the magnetic path area can be increased and the magnetic characteristics can be improved. Further, the coaxiality with the movable core 40 can be improved by setting the length of the yoke 62 in the axial direction large.

  In the above-described embodiment, the cylindrical portion 68 of the yoke 62 has an upper cylindrical portion 68a and a lower cylindrical portion 68b. However, either the upper cylindrical portion 68a or the lower cylindrical portion 68b is used. A shape having only one side may be used, and thereby the movable core 40 may be guided.

  Between the housing 14 and the coil 34, a resin sealing body 74 for molding the outer peripheral surface of the coil 34 and the coil bobbin 56 is provided. The resin sealing body 74 is made of resin continuously to a coupler portion 76 to be described later. It is integrally formed with the material.

  An O-ring having a substantially elliptical cross section is mounted between the flange 57a of the coil bobbin 56 and the housing 14 via an annular groove formed in the flange 57a. Further, between the upper surface of the annular flange portion 70 of the yoke 62 and the resin sealing body 74 and between the lower surface of the annular flange portion 70 and the valve body 18, respectively, O Rings 78b and 78c are attached.

  The end portion of the housing 14 is pressed by an upper portion of the valve body 18 by being pressurized by a not-shown crimping means, and is integrally connected.

  A coupler portion 76 for energizing the coil 34 is provided on a side portion of the housing 14, and the coupler portion 76 is provided so that a terminal portion 77 a of a terminal 77 electrically connected to the coil 34 is exposed. It is done. A mounting stay 80 that is bent in a substantially L shape is fixed to the side portion of the housing 14 opposite to the coupler portion 76.

  The electromagnetic valve 10 according to the embodiment of the present invention is basically configured as described above. Next, the operation and effects thereof will be described.

  When the coil 34 of the solenoid unit 12 is not energized, as shown in FIG. 1, the ball 32 is seated on the lower seat 30 and the inlet port 20 and the outlet port 24 are not in communication. The outlet port 24 and the discharge port 28 are in communication with each other.

  Therefore, by energizing a power source (not shown) and energizing the coil 34, the solenoid unit 12 is excited and turned on, and a magnetic circuit 82 as shown in FIG. 9 is generated. The magnetic circuit 82 has a magnetic flux that returns to the housing 14 via the housing 14, the yoke 62, the movable core 40, and the fixed core portion 54 in order.

  Due to the electromagnetic force generated by the magnetic circuit 82, the movable core 40 is attracted to the fixed core portion 54 overcoming the pressing force of the return spring 36. Then, the shaft 38 integrally connected to the movable core 40 is displaced upward under the guide action of the cylindrical portion 68 of the yoke 62, and the small diameter shaft portion 38 a of the shaft 38 is separated from the ball 32. Accordingly, the force that urges the ball 32 toward the lower side seating portion 30 disappears, and the ball 32 is separated from the lower side seating portion 30 by the pressing force of the pressure fluid (pressure oil) introduced from the inlet port 20, and the upper side. Sit on the seat 48.

  When the ball 32 is separated from the lower side seating portion 30 and seated on the upper side seating portion 48, the inlet port 20 and the outlet port 24 communicate with each other (see FIG. 2), and the ball 32 is introduced from the inlet port 20. The pressure fluid is led to an external fluid device (not shown) through the outlet port 24.

  When the energization of the solenoid portion 12 to the coil 34 is stopped, the electromagnetic force disappears, and the movable core 40 and the shaft 38 are displaced downward under the action of the spring force of the return spring 36 to press the ball 32. Thus, the valve 32 returns to the closed state in which the ball 32 is seated on the lower side seating portion 30.

  In the present embodiment, by making the cross-sectional shape of the coil 34 wound around the coil bobbin 56 constituting the solenoid portion 12 square, the gap generated between the stacked coils 34 can be made extremely small. Therefore, for example, when compared with a conventional technique in which a solenoid coil having a circular cross section has the same number of turns, the total cross sectional area of the coil 34 (the entire space of the coil 34 wound around the coil bobbin 56) can be set small. .

  Paradoxically, this means that the ratio of the conductor cross-sectional area to be tightened in the winding space of the coil 34, that is, the conductor occupation ratio can be set larger than that of the circular cross-section. Therefore, since the winding space of the coil 34 can be reduced, the shape of the coil bobbin 56 can be reduced, and ultimately the solenoid unit 12 as a whole can be reduced in size.

  Further, for example, when the winding space is the same as that of the solenoid coil having a circular cross section, in the present embodiment using the coil 34 having a square cross section, the number of turns on the coil bobbin 56 can be increased. The attraction force (electromagnetic force) generated at 12 can be increased.

  Furthermore, in this embodiment, since the winding space of the coil 34 can be reduced, the continuous total dimension (full length) of the coil 34 can be reduced. Therefore, the resistance value of the coil 34 can be reduced, and the power consumption consumed when the coil 34 is energized can be suppressed.

  For example, when the coil 34 having a circular cross section is formed so as to have the same resistance value as that of the coil having a circular cross section, in the present embodiment, the number of windings on the coil bobbin 56 can be set to a large value. Electromagnetic force) can be improved.

  Furthermore, in the present embodiment, since the contact surface between the stacked coils 34 is a surface contact, the single line occupancy in the winding space can be set larger than that of the coil having a circular cross section. it can.

  Therefore, the gap generated between the stacked coils 34 can be made extremely small, and the occupation density of each coil 34 per unit volume of the winding space can be improved. Thereby, the heat conductivity (heat dissipation) in a winding space can be improved. For example, when applied to an electromagnetic valve that is used in an environment where the ambient temperature is lower than the coil heat generation temperature, the heat dissipation is improved. Therefore, in addition to the fact that the resistance value of the coil 34 can be set small as described above, further energization is performed. Heat generation in the coil 34 at the time of heat generation can be reduced, and therefore the resistance value can be further reduced.

  Furthermore, the solenoid part 12 including the coil 34 formed in a square cross section can be suitably applied as a vehicle-mounted solenoid valve. In-vehicle components are generally limited to a minimum applied voltage (for example, 8 V) by a battery voltage. And since it is requested | required as a vehicle-mounted solenoid valve to ensure the minimum magnetomotive force (electric current value), for example, when the same magnetic circuit is used, a maximum resistance value will be decided inevitably. Here, since the resistance value of the coil 34 generally increases as the temperature of the coil 34 increases, the maximum resistance value must be a value that also takes into account the increased resistance value. For example, if the maximum resistance value is set without taking this rising resistance value into consideration, the necessary current value cannot be obtained, and the minimum magnetomotive force may not be obtained. That is, when used as an in-vehicle solenoid valve, it is necessary to secure a magnetomotive force (current value) even if the resistance value of the coil 34 is energized through the solenoid unit 12 and the temperature of the coil 34 is increased.

  Therefore, if the resistance value of the coil 34 and the resistance value of the coil 34 during energization heat generation are low, a high current value can be secured by Ohm's law, which is extremely beneficial. That is, by making the cross-sectional shape of the coil 34 square, for example, in the solenoid part 12 that can obtain the same magnetomotive force, the resistance value of the coil 34 is reduced to reduce power consumption. The amount of heat generated by the coil 34 during energization decreases, and the resistance value during energization heat generation can be reduced.

  As a result, since the resistance value of the coil 34 during energization heat generation can be reduced to ensure a high current value, it can be suitably used as an in-vehicle electromagnetic valve in which the minimum applied voltage is limited. Further, for example, the solenoid unit 12 having the coil 34 having a square cross section has a current value that is higher than that of the other solenoid unit having the same minimum magnetomotive force formed by a coil having a circular cross section. Since the number of turns on the coil bobbin 56 can be reduced, the size can be further reduced.

  Furthermore, in this embodiment, since the nonmagnetic layer 64 is formed on the entire outer surface of the movable core 40 by the surface modification process, it functions as a magnetic gap in the magnetic circuit 82 generated by energizing the coil 34. Can be made.

  Further, since the nonmagnetic layer 64 is formed on the entire outer surface of the movable core 40, it can be easily formed to a predetermined dimension by managing the outer diameter of only the movable core 40. Accordingly, the magnetic gap formed by the clearance between the yoke 62 and the movable core 40 can be managed with high accuracy, and extremely good magnetic characteristics can be obtained.

  Further, the nonmagnetic layer 64 is formed on the entire outer surface of the movable core 40, so that the movable core 40 is prevented from sticking to the inner wall surface of the yoke 62, and the nonmagnetic thin film used in the prior art or A nonmagnetic member (for example, a nonmagnetic pipe) or the like becomes unnecessary.

  Accordingly, since the non-magnetic thin film is not required, the film thickness dimension of the non-magnetic thin film that affects the outer diameter dimension of the movable core 40 is not controlled, and peeling, swelling, unevenness, pinholes, etc. Since there is no possibility of occurrence, durability can be improved and a product having good quality can be obtained.

  Furthermore, the thickness of the nonmagnetic layer 64 formed on the entire outer surface of the movable core 40 is made thin or thick, so that the size of the magnetic gap (the outer peripheral surface of the movable core 40 and the inner wall surface of the yoke 62 is reduced). Clearance) can be adjusted. As a result, a desired attractive force corresponding to the size of the magnetic gap can be obtained. When the magnetic gap is set as small as possible without adversely affecting the slidability, the tilt of the movable core 40 that is displaced toward the fixed core portion 54 side can be suppressed, and stable magnetic characteristics can be obtained. .

  Furthermore, in the present embodiment, by providing the yoke 62 with the cylindrical portion 68 extending in the axial direction along the outer peripheral surface of the movable core 40, the stable guide function of the movable core 40 can be exhibited. In this case, since the nonmagnetic layer 64 is formed on the entire outer surface of the movable core 40, sticking to the yoke 62 is prevented, and good slidability of the movable core 40 with respect to the inner wall surface of the yoke 62 is obtained. be able to. Since the sliding surface of the movable core 40 with respect to the yoke 62 is hardened (hardened) by the nonmagnetic layer 64 than the magnetic layer on the inner surface, good sliding characteristics can be obtained.

It is a longitudinal cross-sectional view along the axial direction of the solenoid valve which concerns on embodiment of this invention. It is a longitudinal cross-sectional view which shows the valve opening state which the ball | bowl separated from the lower side seating part, and was seated on the upper side seating part by exciting the solenoid part of the solenoid valve shown in FIG. FIG. 2 is a partially enlarged longitudinal sectional view of the coil shown in FIG. 1. It is a partial expanded longitudinal cross-sectional view which shows the state from which the flange formed in the coil bobbin was removed. It is a partial expanded longitudinal cross-sectional view of the solenoid valve which concerns on other embodiment by which the coil of rectangular cross section was wound with respect to the coil bobbin. FIG. 6 is a partially enlarged longitudinal sectional view of the coil shown in FIG. 5. It is an enlarged vertical sectional view when the nonmagnetic layer formed on the entire outer surface of the movable core is thin. It is an enlarged vertical sectional view when the nonmagnetic layer formed on the entire outer surface of the movable core is thick. It is a partially omitted enlarged explanatory view showing a magnetic circuit formed in a solenoid part. It is the partial expanded longitudinal cross-sectional view by which the coil which concerns on a prior art was wound by the coil bobbin.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Solenoid valve 12 ... Solenoid part 14 ... Housing 16 ... Valve mechanism part 18 ... Valve body 20 ... Inlet port 22 ... Communication path 24 ... Outlet port 26 ... Space part 28 ... Discharge port 29, 44 ... Valve seat member 30 ... Lower part Side seating part 32 ... Ball 34, 34a ... Coil 36 ... Return spring 38 ... Shaft 40 ... Movable core 42 ... Stepped hole 46 ... Through hole 48 ... Upper side seating part 52 ... Recessed part 54 ... Fixed core part 56 ... Coil bobbin 57a , 57b ... flange 58 ... passage 60 ... clearance 62 ... yoke 64 ... nonmagnetic layer 68 ... cylindrical part 70 ... annular flange part 74 ... resin sealing body 76 ... coupler part 82 ... magnetic circuit

Claims (10)

A solenoid valve main body including a valve body having an inlet port and an outlet port through which pressure fluid flows and a housing; and
A coil disposed inside the housing and wound around a coil bobbin; a yoke coupled to one end of the housing; a movable core that is attracted to the fixed core portion under an energizing action on the coil; and the fixed core portion A solenoid part having a spring member interposed between the movable core and the movable core for returning the movable core to an initial position;
A valve mechanism having a shaft coupled to the movable core and displaced integrally with the movable core; and a valve body that opens and closes a communication path between the inlet port and the outlet port under the displacement action of the shaft;
With
The solenoid valve according to claim 1, wherein the coil has a square cross section. The solenoid valve according to claim 1, wherein
The solenoid valve according to claim 1, wherein the solenoid valve is mounted on a vehicle. The solenoid valve according to claim 1, wherein
The solenoid valve according to claim 1, wherein the coil bobbin is formed with an annular flange projecting radially outward only at one end or the other end along the axial direction of the coil bobbin. The solenoid valve according to claim 3,
One end part or the other end part along the axial direction of the coil bobbin in which the annular flange is not formed is covered with a sealing body made of a resin material. The solenoid valve according to claim 1, wherein
A solenoid valve, wherein a nonmagnetic layer having a predetermined thickness is formed on an outer surface of the movable core. A solenoid valve main body including a valve body having an inlet port and an outlet port through which pressure fluid flows and a housing; and
A coil disposed inside the housing and wound around a coil bobbin; a yoke coupled to one end of the housing; a movable core that is attracted to the fixed core portion under an energizing action on the coil; and the fixed core portion A solenoid part having a spring member interposed between the movable core and the movable core for returning the movable core to an initial position;
A valve mechanism having a shaft coupled to the movable core and displaced integrally with the movable core; and a valve body that opens and closes a communication path between the inlet port and the outlet port under the displacement action of the shaft;
With
The electromagnetic valve is characterized in that the coil is formed in a rectangular cross section. The solenoid valve according to claim 6, wherein
The solenoid valve according to claim 1, wherein the solenoid valve is mounted on a vehicle. The solenoid valve according to claim 6, wherein
The solenoid valve according to claim 1, wherein the coil bobbin is formed with an annular flange projecting radially outward only at one end or the other end along the axial direction of the coil bobbin. The solenoid valve according to claim 8,
One end part or the other end part along the axial direction of the coil bobbin in which the annular flange is not formed is covered with a sealing body made of a resin material. The solenoid valve according to claim 6, wherein
A solenoid valve, wherein a nonmagnetic layer having a predetermined thickness is formed on an outer surface of the movable core.

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